But the total number of defamation cases brought rose by only 4%, from 83 cases in the year ending May 31 last year to 86 in the 12 months to the end of this May, reported the BBC.
Experts had predicted that there would be a dramatic jump in online defamation cases following the birth of social networking platforms such as Facebook and Twitter.
Meanwhile, the Libel Reform Campaign group said smaller website operators needed more legal backing to protect themselves against actions brought by what it described as "corporate bullies." With businesses under increasing financial pressure, many are increasingly using litigation in order to protect their reputation.
Barrister Korieh Duodu, a media specialist with law firm Addleshaw Goddard LLP, said: "Social media tools have over a billion users worldwide and are growing rapidly in popularity.
"Nevertheless, they can present a huge problem for individuals and corporates trying to protect their reputations from harmful user-generated content."
However, social networking websites are also challenging privacy laws.
According to a report by the Telegraph, more than 75,000 Twitter users broke a High Court gagging order obtained in May by the footballer Ryan Giggs to suppress details of his alleged affair with model Imogen Thomas. John Hemming, the Lib Dem MP for Birmingham Yardley, then disclosed details of the affair under parliamentary privilege, saying it was “obviously impractical” to imprison everyone who breached the super-injunction.
In response to calls for tighter regulation of social networks, Twitter has stated a bias towards free speech, saying that “the tweets must flow”.
“We strive not to remove Tweets on the basis of their content,” Twitter said.
“Technology creates new ways for people to interact with each other,” said Eric Goldman, a law professor at Santa Clara University in California, in a report by the New York Times. “You have to figure out if old law maps to new interactions.”
Twitter is an especially vexing new tool. It prompts ordinary people who use it to create public personas and it can put celebrities, including religious leaders, in direct contact with a large and sometimes unruly following, including some who insist on using pseudonyms.
Mr Duodu said those who provide user-generated content on the Internet should be held more accountable for what they write, through stricter regulation.